Rocket hold back and tube closure

ABSTRACT

This invention comprises a plastic insert which is inserted into the rear end of a missile and acts as a detent to retain the missile in the launch tube as well as a protective end closure for both the missile and launch tube.

United States Patent [191 Ricks ROCKET HOLD BACK AND TUBE CLOSURE [75] Inventor: Earl C. Ricks, Huntsville, Ala.

[73] Assignee: The United States of America as represented by the Secretary of The Army, Washington, DC.

[22] Filed: Nov. 28, 1972 [21] Appl. No.: 310,065

[52] US. Cl 89/1307, 89/1814, 89/1817 [51] Int. Cl F411 3/04 [58] Field of Search 89/1806, 1.807, 1.813,

[56] References Cited UNITED STATES PATENTS 3,166,979 l/l965 Draim l02/49.7 X

[111 3,811,360 [451 May 21-, 1974 3,194,] 19 7/1965 Robert et al l02/49.7 X 3,398,639 8/1968 Apotheloz 89/].807 2,972,933 2/1961 Guthrie et al 89/1817 FOREIGN PATENTS OR APPLICATIONS 996,829 6/1965 Great Britain 89/1807 1,182,275 2/1970 Great Britain 89/1806 Primary Examiner-Samuel W. Engle Attorney, Agent, or Firm-Edward J. Kelly; Herbert Berl; Herbert H. Murray [5 7] ABSTRACT This invention comprises a plastic insertwhich is inserted into the rear end of a missile and acts as a detent to retain the missile in the launch tube as well as a protective end closure for both the missile and launch tube.

1 Claim, 2 Drawing Figures ROCKET HOLD BACK AND TUBE CLOSURE BACKGROUND OF THE INVENTION Launchers for light shoulder fired missiles must be very light in weight, be able to withstand internal pressures of around 800 psi, be able to withstand both end and flat drop tests of four feet in height and provide an environmental seal for the missile inside. These factors present two major interface problems. One is to provide a detent that will hold the missile during a four foot drop on the end, and then be able to release the missile at the'time of firing with a minimum force. The other problem is the electrical umbilical from the firing mechanism on the outside of the launcher to the firing squib in the missile motor and to charge the warhead capacitor.

An object of this invention is to provide a hold back closure which performs both the detent function and an environmental closure for the launch tube.

Another object of the invention is to provide a hold back closure having embedded therein wires for connection between the missile warhead capacitor, the firing squib and'the external firing mechanism.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. I is a section of the rear portion of the missile and launcher showing the device of the invention installed.

FIG. 2 is a similar view immediately after firing showing the device of the invention being blown out.

DETAILED DESCRIPTION OF THE INVENTION Referring now to the drawings indicates the rear portion of a launch tube. The rear portion 12 of a missile mounted within the launch tube 10 is provided with the conventional exhaust nozzle 14. The hold back closure member 16 is shown in FIG. I mounted within the nozzle 14.

The hold back closure member 16 has an outer surface 18 contoured to fit within the venturi shaped inner surface 20 of the nozzle 14. The innermost end of closure member 16 is dome shaped as illustrated at 22 in FIG. I. The outermost end 24 of the closure member I6 is turned back to form an inwardly extending flange 26 which fits around the outside of the rear portion 28 of the launch tube 10. The closure member 16 is made of polyethylene, nylon or other similar material.

The igniting squib 30 for the missile motor is mounted on the dome shaped inner end of the closure member I6.

Two annular grooves 32 and 34 are formed at the rear end of closure member 16, one facing rearwardly and the other radially outward. The grooves 32 and 34 are filled with either a resilient material such as hard rubber or a crushable material such as polyeurathane as illustrated at 36 and 38 which projects outwardly beyond the groove to provide cushioning if the assembly is dropped.

2 Conductors 40 from the squib 30 are embedded within closure member 16 and lead to a pin type con- 1 nector 42 on the forwardly projecting flange 26. Similarly, conductors 44 connected to connector 42 lead to the capacitor in the warhead of the missile. The pin connector 42 mates with a female connector 46 mounted on the launch tube 10 when the closure member 16 is inserted to provide connection to the firing mechanism (not shown) on the outer surface of the launch tube 10.

The end closure member 16 of the present invention is inserted by means of a mandrel, not shown. The mandrel first contacts the domed end 22 of the device and deforms it by increasing the curvature of the dome thus pulling inwardly the edge 50. The mandrel is provided with a shoulder which contacts the internal shoulder 52 of the device thus pushing the device into the nozzle of the missile. The missile is then inserted into the launch tube 10 and the flange 26 slides over the end of the launch tube 10. The pin connector 42 mates with the female connector 46 to complete the electrical connections. When the mandrel is removed the domed end of the end closure member 16 springs back to its normal configuration permitting edge 50 to move outwardly to provide a detent to prevent forward movement of the missile 12 relative to the tube 10.

When the missile is fired, the pressure in the rocket motor applied against the domed end 22 reverses the curvature as illustrated in FIG. 2 to draw theedge 50 inward and the whole assembly is blown out ofthe rear end of the missile.

I claim:

1. In a rocket hold back and launch tube closure assembly the combination comprising:

a launch tube,

a rocket received within said launch tube and having a discharge nozzle with a constricted throat portion at its rear end,

a one piece relatively rigid structure of resilient material having an outer surface shaped to conform to the inner surface of the constricted throat portion of the nozzle of said rocket,

a forward end on said closure assembly closing the rocket motor nozzle,

a flange on said closure assembly extending forwardly from the rear portion of said closuremember and adapted to fit close around the outer surface of said launch tube,

an igniting squib mounted on the inner dome shaped end of said closure assembly,

a pin type connector mounted on the forwardly extending flange of said closure assembly adapted to mate with a female connector on said launch tube, and

wiring embedded in said closure member connecting said igniting squib with said pin type connector. 

1. In a rocket hold back and launch tube closure assembly the combination comprising: a launch tube, a rocket received within said launch tube and having a discharge nozzle with a constricted throat portion at its rear end, a one piece relatively rigid structure of resilient material having an outer surface shaped to conform to the inner surface of the constricted throat portion of the nozzle of said rocket, a forward end on said closure assembly closing the rocket motor nozzle, a flange on said closure assembly extending forwardly from the rear portion of said closure member and adapted to fit close around the outer surface of said launch tube, an igniting squib mounted on the inner dome shaped end of said closure assembly, a pin type connector mounted on the forwardly extending flange of said closure assembly adapted to mate with a female connector on said launch tube, and wiring embedded in said closure member connecting said igniting squib with said pin type connector. 